forstio/source/stream_endian.h

141 lines
3.2 KiB
C++

#pragma once
#include "buffer.h"
#include "error.h"
#include <cstdint>
#include <cstring>
namespace gin {
template <typename T, size_t size = sizeof(T)> class ShiftStreamValue;
template <typename T> class ShiftStreamValue<T, 1> {
public:
inline static Error decode(T &val, Buffer &buffer) {
uint8_t& raw = reinterpret_cast<uint8_t&>(val);
return buffer.pop(raw, sizeof(T));
}
inline static Error encode(const T &val, Buffer &buffer) {
uint8_t& raw = reinterpret_cast<uint8_t&>(val);
return buffer.push(raw, sizeof(T));
}
inline static size_t size() { return sizeof(T); }
};
template <typename T> class ShiftStreamValue<T, 2> {
public:
inline static Error decode(T &val, Buffer &buffer) {
if (buffer.readCompositeLength() < sizeof(T)) {
return recoverableError("Buffer too small");
}
uint16_t& raw = reinterpret_cast<uint16_t&>(val);
uint8_t buf[sizeof(T)] = 0;
Error error = buffer.pop(buf, sizeof(T));
if(error.failed()){
return error;
}
for (size_t i = 0; i < sizeof(T); ++i) {
raw |= buf[i] << (i * 8);
}
return noError();
}
inline static Error encode(const T &val, Buffer &buffer) {
if (buffer.writeCompositeLength() < sizeof(T)) {
return recoverableError("Buffer too small");
}
uint16_t raw;
memcpy(&raw, &val, sizeof(T));
for (size_t i = 0; i < sizeof(T); ++i) {
buffer.write(i) = raw >> (i * 8);
}
buffer.writeAdvance(sizeof(T));
return noError();
}
inline static size_t size() { return sizeof(T); }
};
template <typename T> class ShiftStreamValue<T, 4> {
public:
inline static Error decode(T &val, Buffer &buffer) {
if (buffer.readCompositeLength() < sizeof(T)) {
return recoverableError("Buffer too small");
}
uint32_t raw = 0;
for (size_t i = 0; i < sizeof(T); ++i) {
raw |= buffer.read(i) << (i * 8);
}
memcpy(&val, &raw, sizeof(T));
buffer.readAdvance(sizeof(T));
return noError();
}
inline static Error encode(const T &val, Buffer &buffer) {
if (buffer.writeCompositeLength() < sizeof(T)) {
return recoverableError("Buffer too small");
}
uint32_t raw;
memcpy(&raw, &val, sizeof(T));
for (size_t i = 0; i < sizeof(T); ++i) {
buffer.write(i) = raw >> (i * 8);
}
buffer.writeAdvance(sizeof(T));
return noError();
}
inline static size_t size() { return sizeof(T); }
};
template <typename T> class ShiftStreamValue<T, 8> {
public:
inline static Error decode(T &val, Buffer &buffer) {
if (buffer.readCompositeLength() < sizeof(T)) {
return recoverableError("Buffer too small");
}
uint64_t raw = 0;
for (size_t i = 0; i < sizeof(T); ++i) {
raw |= buffer.read(i) << (i * 8);
}
memcpy(&val, &raw, sizeof(T));
buffer.readAdvance(sizeof(T));
return noError();
}
inline static Error encode(const T &val, Buffer &buffer) {
if (buffer.writeCompositeLength() < sizeof(T)) {
return recoverableError("Buffer too small");
}
uint64_t raw;
memcpy(&raw, &val, sizeof(T));
for (size_t i = 0; i < sizeof(T); ++i) {
buffer.write(i) = raw >> (i * 8);
}
buffer.writeAdvance(sizeof(T));
return noError();
}
inline static size_t size() { return sizeof(T); }
};
template <typename T> using StreamValue = ShiftStreamValue<T>;
} // namespace gin